textproduct: Rapid City

KEY MESSAGES

- Active northwest flow will persist through the week with unsettled weather.

- Cooler temperatures persist through Wednesday before warming trend into the weekend.

UPDATE

Issued at 954 PM MDT Mon May 4 2026

No significant forecast changes needed with this evening's update. Things still looks quite cool and unsettled through Tuesday evening with CAMs continuing to advertise at least isolated shower potential, but QPF probabilities are quite low so not much of any rainfall is expected. Some showers will fall as snow over the Black Hills and perhaps northeastern Wyoming, but even at the higher elevations of the Black Hills where temperatures will be coldest, less than 2 inches are expected where it does snow. Wednesday will still lean cool (highs in the 50s), before temperatures noticeably warm from Thursday into the weekend (60s and low 70s).

DISCUSSION

(This Evening Through Monday) Issued at 113 PM MDT Mon May 4 2026

Water vapor imagery shows active northwestern flow across the Northern Plains. Closed upper low is centered over western Ontario with another closed low over central CA coast. The surface cold front pushed through the area around 11z this morning and now stretches from the surface low in central Ontario southwestward through southern NE.

Weak mid-level frontogenesis coupled with steep low-level lapse rates have resulted in scattered showers this afternoon, mainly south of I-90. Given dry boundary layer and weak forcing, expect minimal precipitation amounts.

Well-mixed boundary layer with 35-40 knot winds atop the boundary layer will support gusts up to 45-50 MPH this afternoon across northwestern SD. A Wind Advisory remains in effect for portions of the northwestern SD plains through 6 PM MDT.

Active northwest flow persists through mid-week with cooler than average temperatures (5-10F below normal) before warmer air filters back into the region with seasonable to above average (~5-10F) temperatures for the latter half of the week into the weekend. Showers and thunderstorms possible Saturday as upper shortwave trough drops into the Northern Plains.

AVIATION

(For the 12Z TAFS Through 12Z Wednesday Morning) Issued At 520 AM MDT Tue May 5 2026

Low clouds (CIGS 4-6kft) will persist today and tonight across the plains...and some areas of MVFR CIGS will be possible across the Black Hills. Isolated rain showers will be possible today, with some snow showers across the Black Hills and portions of NE WY.

UNR WATCHES/WARNINGS/ADVISORIES

SD...None. WY...None.